`echo -n` is non-portable and does not work under some operating
systems, such as OS X. Replace it with printf.
Signed-off-by: Lukas Fleischer <lfleischer@calcurse.org>
The existence of a ".git" directory is not a sufficient condition to be
sure we are in a Git repository. Only overwrite the version information
file if `git describe` returns a non-empty string.
Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>
Introduce a script to auto-generate version strings. Use `git describe`
to create descriptive version strings when building from a Git checkout,
use ".version" files for release tarballs.
Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>
